Bag



KS B. MILLER Nov. 8,1966

BAG

2 Sheets-Sheet l Filed April 19, 1965 KB. MILLER Nov. 8, 1966 BAG 2 Sheets-Sheet 2 Filed April 19, 1965 FIG.

FIC-.4

United States Patent O 3,283,994 BAG Keeth B. Miller, Terre Haute, Ind., assignor to Bemis Company, Inc., a corporation of Missouri Fiied Apr. 19, 1965, Ser. No. 449,199 Claims. (C1. 229-55) This invention relates to bags, more particularly to bags made of flexible heat-scalable sheet plastic material, such as polyethylene, for example, used for packaging loose material such as powdered or granular material, for example.

Among the several objects of the invention may be noted the provision of an improved construction for a bag, and more particularly a bag made of flexible heatscalable sheet plastic material such as polyethylene, adapted to maintain the contents of the bag tightly sealed until the bag is opened at the top to obtain some of the contents, and having means whereby after the bag has been opened the top may be drawn closed, with the arrangement such that the bag may be reopened and reclosed as many times as needed until the contents have been completely used; the provision of a bag construction such as described in which the means for drawing the top of the bag closed comprises a draw cord (this term being intended to include a tape as well as an actual cord); the provision of a bag construction such as described having a strong top closure resistant to rupture; the provision of a bag construction such as described comprising an inner bag within an outer bag, the means for drawing the top of the bag closed being associated with the outer bag, so that, even if there should be any rupture of the top portion of the outer bag (where rupture is most apt to occur) prior to the opening of the top of the bag, the contents remain sealed in the inner bag. Other objects and features wil-l be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated:

FIG. 1 is a perspective illustrating generally diagrammatically the manufacture of bags of this invention;

FIGS. 2 and 3 are enlarged fragmentary transverse sections taken on lines 2 2 and 3-3, respectively, of FIG. 1;

FIG. 4 is a View in elevation illustrating a completed bas;

FIG. 5 is a view of the top of the FIG. 4 bag beforeA it is filled;

FIG. 6 is an enlarged fragmentary section taken on line 6 6 of FIG. 4, showing the bag walls separated' and FIG. 7 is an enlarged view from the top of the FIG. 4 bag showing the appearance of the bag after it has been filled.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to FIGS. 1-3 of the drawings, there is indicated at 1 a composite web of flexible heat-sealable sheet plastic material, such as polyethylene, which comprises an inner web 3 of such material folded upon itself as will be described and an outer web 5 folded upon itself and around the outside of the inner web as will be described.

The inner web 3 is folded on longitudinal fold lines 7, 9 and 11 (see FIGS. 2 and 3) to have superimposed walls 13 and 15 joined along one edge of the composite web 1 by an intucked gusset which is designated in its 3,283,994 Patented Nov. 8, 1966 ICC entirety by the reference numeral 17. As will be under stood, this gusset comprises a panel 19 joined to the wall 13 at fold 7 and a panel 21 joined to the wall 15 at fold 9, the two panels of the gusset being joined at fold 11, which is the center fold of the gusset. As appears in FIGS. 1-3, wall 15 may be slightly wider than wall 13.

The outer web 5 is folded on longitudinal fold lines 23, 25 and 27 (see FIGS. 2 and 3) to have first and second walls 29 and 31 lying on the outside of walls 13 and 15 of the inner web 3 joined along the stated edge of the composite web 1 by an intucked gusset designated in its entirety by the reference numeral 33. This gussetv 33 comprises a panel 35 joined to the wall 29 at fold 23 and a panel 37 joined to the wall 31 at fold 25, the two panels of the gusset 33 being joined at fold 27, which is lthe center fold of the gusset 33. In the initial flat unfolded condition of the inner and outer webs 3 and 5, the outer web 5 is wider than the inner web 3. When the outer web 5 is folded and combined with the inner web 3, the edges 39 and 41 of walls 13 and 29 opposite the gussets are brought generally into register, and the edges 43 and 45 of walls 15 and 31 opposite the gussets are also brought generally into register with the result that walls 29 and 31 of the outer web as folded are wider than the respective walls 13 and 15 of the inner web as folded, and have portions 47 and 49 which eX- tend beyond the margins 7 and 9 of walls 13 and 15 of the inner web along the stated edge of the composite web 1.

As will be understood, the webs 3 and 5 may be supplied in fiat unfolded condition from respective rolls of web material, and folded and combined by suitable conventional folding means. As shown in FIG. 1, the composite web 1 (consisting of the folded webs 3 and 5) is intermittently fed forward toward the right in bag width intervals by a pair of intermittently driven feed rolls 51, 53.

As the composite web 1 is fed forward, notches 55 are cut in the portions 47 and 49 of the walls 29 and 31 of the outer web 5 and in the portions of panels 35 and 37 of the gusset 33 of the outer web 5 which extend outward beyond the margins 7 and 9 of the walls 13 and 15 of the inner web 3, these notches being spaced at bag width intervals. The cutting of these notches may be effected by means such as indicated at 57 which operates during dwell intervals of web 1 (While the web is stationary) between successive feed intervals of the feed rolls 51, 53. web 5 only; there is no cutting of the inner web 3.

Following the operation of cutting the notches 55, draw cords 59 and 61 are introduced into the folds 23 and 25 Where the panels 35 and 37 of the gusset 33 of the outer web join the walls 29 and 31 of the outer web. As shown in FIG. 1, cord 59 is introduced into the fold 23 between walls 29 and 13 of the composite web 1, and cord 61 is introduced into the fold 25 between walls 31 and 15 of the composite web, walls 29 and 13 being free of one another at this stage of operations, and Walls 31 and 15 likewise being free of one another at this stage of operations. Cord 59 leads in between walls 29 and 13 from a suitable supply (not shown) and is guided around a pulley 63 on a Hat arm `65 reaching in between walls 29 and 13 to extend forward (toward the right) in the fold 23. Similarly, cord 61 leads in between the walls 31 and 15 from a suitable supply (not shown) and is guided around a pulley 67 on a at arm 69 reaching in between walls 31 and 15 to extend forward in the fold 25.

After the cords 59 and 61 have been introduced into the folds 23 and 25, hems for containing the cords within the folds are formed by heat-sealing portions 47 and 49 of walls 29 and 31 t0 the panels 35 and 37 of the gusset The notches are provided in the outer 'loop L including portions of both cords.

33 on lines 71 and 73 lying inward of the cords extending longitudinally of the composite Web 1. The seals on lines 71 and 73 are preferably interrupted seals so as to minimize the possibility of tearing along the lines of the seals, and may be made as shown in FIG. 1 by means of upper and lower sealing bars 75 and 77, constructed to form interrupted seals. These bars are suitably actuated to form the seals at 71 and 73 during the dwell intervals of the composite web. FIG. 3 shows the bars 75 and 77 clamped on the web to form the seals 71 and 73, with a separator plate 79 to preclude heat-sealing together of the panels 35 and 37 of the gusset 33.

At the -time of forming the hem seals 71 and 73, walls 29 and 13 may be heat-sealed together along a line 81 extending longitudinally of the composite web adjacent their free edges 41 and 43, and walls 15 and 31 may be heat-sealed together along a line 83 extending longitudinally of the composite web adjacent their free edges. This is for the purpose of preventing separation of wall 29 from wall 13, and preventing separation of Wall 31 from wall 15, and defining a bottom mouth for the ultimate bags between walls 13 and 15. This operation may be carried out by means of sealing bars as indicated at S5 and 87 and providing a separa-tor 91 between walls 13 and 15, bars 85 and 87 being operable during dwell intervals of the composite web (like bars 75 and 77).

After the forming of the hem seals 71 and 73, the portions of the cords 59 and 61 which are exposed in the notches 55 are gathered together and pulled out into a The portions of the two cords in the loop are then secured together as by sta-ples 93 at two points spaced along the length of the cords, and the cords are severed between the two points of securernent. This may be effected by suitable stapling and severing means lgenerally indicated at 95 in FIG. 1, operable during dwell intervals of the composite web.

After the loops L have been drawn, stapled and severed, the composite web 1 is heat-sealed and segmented on transverse lines spaced at bag width intervals and intersecting the notches 55 to complete the formation of the bags. As shown in FIG. 1, this may be effected by a hot knife 97 operable during dwell intervals of the composite web.

For carrying out the above method, apparatus such as shown in Ashton et al. U.S. Patent No. 2,897,729, issued August 4, 1959 may be used. FIG.` 1 shows at 223 and 225 rolls the same as shown at 223 and 225 in said patent for insuring feeding forward of the cords, and at 272 a clamping means the same las shown at 272 in said patent for clamping the cords when a loop L is being drawn out.

FIGS. 4-6 illustrate a completed bag B made as above described. The complete bag basically comprises an inner bag 101 and an outer bag 103, the inner bag being disposed Within the outer bag. The inner bag has walls 13a and 15a (derived from walls 13 and 15 of the inner Web 3). Wall 13a may be referred to as the front wall and Wall 15a may be referred to as the back wall. An intucked gusset 17a (derived from gusset 17 of the inner web 3) extends across the top of inner bag 101. The panels of this gusset are designated 19a and 21a. The folds of ythe inner bag which correspond to folds 7, 9 and 11 of the inner web 3 are designated 7a, 9a and 11a. The outer bag 103 has front and back walls 29a and 31a (derived from walls 29 and 31 of the outer web 5) and an intucked gusset- 33a (derived from gusset 33 of the outer web 5) extendingacross the top thereof. The panels of the gusset 33a are designated 35a and 37a. The folds of the ou-ter bag which correspond to folds 23, 25 and 27 of the outer web 5 are designated 23a, 25a, 27a. The fupper portions 47a and 49a of the front and back walls of the outer bag 103 extend upward beyond the upper' margins 7a and 9a of the inner bag 101. Gusset 33a is joined by the folds 23a and 25a at the front and back margins thereof to the upper margins of the front and back Walls 29a and 31a of the outer bag. The top gusset 33a of theouter bag is deeper than the top gusset and is intucked in the top gusset 17a of the inner bag.

As -a result of heat-sealing and segmenting the composite web 1 on lines spaced at bag Width intervals and intersecting the notches 55, the walls 29a, 13a, 15a and 31a of the outer and inner bags are heat-sealed together along the side edges of the bag 101, these heat-sealed side seams of the bag being designated 105. Also, the top corners of the bag have openings or cutouts 55a, each cutout being half of one of the original notches 55. The side seams extend from the bottom of the bag to the bottom of these cutouts. Extending across the top of the bag within the folds 23a and 25a and out of these cutouts 55a are cords 59a and 61a (derived from cords 59 and 61), the ends of the cords which extend out through the cutouts being secured together by the staples 93. The cords are contained in the folds 23a and 25a by the heat seals on lines 71 and 73 which secure the top portions 47a and 49a of the front and back walls of the outer bag to the panels 35a and 37a of the gusset 33a above the top margins 7a and 9a of the front and back walls of the inner bag and below the cords (and also preferably below the cutouts 55a).

The bag B is initially open at the bottom, having a mouth 107 between walls 13a and 15a of the inner bag, and a projecting lip 109 at the bottom of back wall 15a, 31a for facilitating opening the month. Walls 29a and 13a are sealed together at 81 and walls 15a and 31a are sealed together at 83 to prevent their separation thereby to insure proper opening of the mouth 107. After the bag has been filled through said bottom mouth 107, the walls 29a, 13a and 15a, 31a may be closed in any suitable manner, as by heat-sealing. Then the bag is filled, the gussets 33a and 17a spread out generally at, las shown in FIG. 7, the tubular top portions of the outer bag above the lines of seals 71 and 73 which contain the draw cords 59a and 61a extending upward at the front and back of the top of the bag. The cords extend out of these tubular top portions at both ends and are secured together outside said ends by the staples 93.

A filled bag B constructed as above described is apt to be handled by the draw cords, imposing considerable strain on'the bag along the lines of seal 71 and 73. It has Ibeen found, however, that by using interrupted seals at 71 and 73 (as is preferred), the tendency for rupture to occur at these seals is reduced. Moreover, if rupture should occur at these seals, or elsewhere in the outer bag, the inner bag remains intact to retain the contents.

It will be understood that when it is desired to remove part of the contents of a filled lbag B, a slit may be made in the top gusset structure 33a, 17a. Thereafter, the draw cords may be pulled to close the top of the bag.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

i What is claimed is:

1. A bag construction comprising an inner lbag and an outer bag, the inner bag being disposed within the outer bag, the inner bag having front and back walls and an intucked gusset extending across the top thereof, the outer bag having front and back walls which extend upward beyond the upper margins of the front and back walls of the inner bag and an intucked gusset extending across the top thereof, the top gusset of the outer bag being joined by folds at the front and back margins thereof to the upper margins of the front and back walls of the outer bag, the top gusset of the outer bag being deeper than the top gusset of the 'inner bag and being intucked in the top gusset of the inner bag, and draw cord means disposed within said folds above the upper margins of the front and back walls of the inner bag.

2. A bag construction as set forth in claim 1 wherein the top portions of the front and back walls of the outer bag which extend upward beyond the upper margins of the front and back walls of the inner bag are secured to the adjacent portions of the top gusset of the outer bag along lines extending across the -bag above the upper margins of the front and back walls of the inner bag and below the draw cord means.

3. A bag construction as set forth in claim 1 wherein the inner and outer bags are made of heat-scalable material and their front and back walls are heat-sealed together along the side edges thereof.

4. A bag construction as set forth in claim 3 wherein the top portions of the front and back walls of the outer bag which extend upward beyond the upper margins of the front and back walls of the inner bag are secured to the adjacent portions of the top gusset of the outer bag by heat seals along lines extending across the bag above the upper margins of the front and back walls of the inner bag and below the draw cord means.

5. A bag construction comprising an inner bag and an outer bag each of exible heat-sealable sheet plastic material, the inner bag being disposed within the outer bag, the inner bag having front and back walls and an intucked gusset extending across the top thereof, the outer bag having front and back walls which extend upward beyond the upper margins of the front and back walls of the inner .bag and an intucked gusset extending across the top thereof, the top gusset of the outer bag being joined by folds at the front and back margins thereof to the upper margins of the front 4and back walls of the outer bag, the top gusset of the outer bag being deeper than the top gusset of the inner bag and being intucked in the top gusset of the inner bag, the front and back 5 walls of the inner and outer bags being heat-sealed together along the side edges thereof to form bag side seams, the inner bag being open at the bottom for filling, the top portion of the outer bag which extends above the top of the inner bag having openings at the top cor- 10 ners thereof, draw cords disposed in said folds above the upper margins of the front and back walls of the inner bag and extending out of said openings and having their ends secured together, the top portions of the front and back walls of the outer bag which extend upward beyond 15 the upper margins of the front and back walls of the inner bag being secured to the adjacent portions of the top gusset of the outer bag by heat seals along lines extending across the bag above the upper margins of the front and back walls of the inner bag and below the draw cords. 20

References Cited by the Examiner UNITED STATES PATENTS .OSEPl-l R. LECLAIR, Primary Examiner.

DAVID M. BOCKENEK, Examiner. 

1. A BAG CONSTRUCTION COMPRISING AN INNER BAG AND AN OUTER BAG, THE INNER BAG BEING DISPOSED WITHIN THE OUTER BAG, THE INNER BAG HAVING FRONT AND BACK WALLS AND AN INTUCKED GUSSET EXTENDING ACROSS THE TOP THEREOF, THE OUTER BAG HAVING FRONT AND BACK WALS WHICH UPWARD BEYOND THE UPPER MARGINS OF THE FRONT AND BACK WALLS OF THE INNER BAG AND AN INTUCKED GUSSET EXTENDING ACROSS THE TOP THEREOF, THE TOP GUSSET OF THE OUTER BAG BEING JOINED BY FOLDS AT THE FRONT AND BACK MARGINS THEREOF TO THE UPPER MARGINS OF THE FRONT AND BACK WALLS OF THE OUTER BAG, THE TOP GUSSET OF THE OUTER BAG BEING DEEPER THAN THE TOP GUSSET OF THE INNER BAG AND BEING INTUCKED IN THE TOP GUSSET OF THE INNER BAG, AND DRAW CORD MEANS DISPOSED WITHIN SAID FOLDS ABOVE THE UPPER MARGINS OF THE FRONT AND BACK WALLS OF THE INNER BAG. 